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Tixi W, Maldonado M, Chang YT, Chiu A, Yeung W, Parveen N, Nelson MS, Hart R, Wang S, Hsu WJ, Fueger P, Kopp JL, Huising MO, Dhawan S, Shih HP. Coordination between ECM and cell-cell adhesion regulates the development of islet aggregation, architecture, and functional maturation. eLife 2023; 12:e90006. [PMID: 37610090 PMCID: PMC10482429 DOI: 10.7554/elife.90006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Accepted: 07/12/2023] [Indexed: 08/24/2023] Open
Abstract
Pancreatic islets are three-dimensional cell aggregates consisting of unique cellular composition, cell-to-cell contacts, and interactions with blood vessels. Cell aggregation is essential for islet endocrine function; however, it remains unclear how developing islets establish aggregation. By combining genetic animal models, imaging tools, and gene expression profiling, we demonstrate that islet aggregation is regulated by extracellular matrix signaling and cell-cell adhesion. Islet endocrine cell-specific inactivation of extracellular matrix receptor integrin β1 disrupted blood vessel interactions but promoted cell-cell adhesion and the formation of larger islets. In contrast, ablation of cell-cell adhesion molecule α-catenin promoted blood vessel interactions yet compromised islet clustering. Simultaneous removal of integrin β1 and α-catenin disrupts islet aggregation and the endocrine cell maturation process, demonstrating that establishment of islet aggregates is essential for functional maturation. Our study provides new insights into understanding the fundamental self-organizing mechanism for islet aggregation, architecture, and functional maturation.
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Affiliation(s)
- Wilma Tixi
- Department of Translational Research and Cellular Therapeutics, Arthur Riggs Diabetes and Metabolism Research Institute, Beckman Research Institute, City of HopeDuarteUnited States
| | - Maricela Maldonado
- Department of Translational Research and Cellular Therapeutics, Arthur Riggs Diabetes and Metabolism Research Institute, Beckman Research Institute, City of HopeDuarteUnited States
- Department of Biomedical Engineering, College of Engineering, California State University, Long BeachLong BeachUnited States
| | - Ya-Ting Chang
- Department of Translational Research and Cellular Therapeutics, Arthur Riggs Diabetes and Metabolism Research Institute, Beckman Research Institute, City of HopeDuarteUnited States
| | - Amy Chiu
- Department of Translational Research and Cellular Therapeutics, Arthur Riggs Diabetes and Metabolism Research Institute, Beckman Research Institute, City of HopeDuarteUnited States
| | - Wilson Yeung
- Department of Translational Research and Cellular Therapeutics, Arthur Riggs Diabetes and Metabolism Research Institute, Beckman Research Institute, City of HopeDuarteUnited States
| | - Nazia Parveen
- Department of Translational Research and Cellular Therapeutics, Arthur Riggs Diabetes and Metabolism Research Institute, Beckman Research Institute, City of HopeDuarteUnited States
| | - Michael S Nelson
- Light Microscopy Core, Beckman Research Institute, City of HopeDuarteUnited States
| | - Ryan Hart
- Department of Neurobiology, Physiology and Behavior, University of California, DavisDavisUnited States
| | - Shihao Wang
- Department of Cellular and Physiological Sciences, Life Sciences Institute, University of British ColumbiaVancouverCanada
| | - Wu Jih Hsu
- Department of Cellular and Physiological Sciences, Life Sciences Institute, University of British ColumbiaVancouverCanada
| | - Patrick Fueger
- Department of Molecular & Cellular Endocrinology, Arthur Riggs Diabetes and Metabolism Research Institute, Beckman Research Institute, City of HopeDuarteUnited States
| | - Janel L Kopp
- Department of Cellular and Physiological Sciences, Life Sciences Institute, University of British ColumbiaVancouverCanada
| | - Mark O Huising
- Department of Neurobiology, Physiology and Behavior, University of California, DavisDavisUnited States
- Department of Physiology and Membrane Biology, School of Medicine, University of California, DavisDavisUnited States
| | - Sangeeta Dhawan
- Department of Translational Research and Cellular Therapeutics, Arthur Riggs Diabetes and Metabolism Research Institute, Beckman Research Institute, City of HopeDuarteUnited States
| | - Hung Ping Shih
- Department of Translational Research and Cellular Therapeutics, Arthur Riggs Diabetes and Metabolism Research Institute, Beckman Research Institute, City of HopeDuarteUnited States
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Ganchala D, Pinto-Benito D, Baides E, Ruiz-Palmero I, Grassi D, Arevalo MA. Kif21B mediates the effect of estradiol on the morphological plasticity of mouse hippocampal neurons. Front Mol Neurosci 2023; 16:1143024. [PMID: 37078090 PMCID: PMC10106616 DOI: 10.3389/fnmol.2023.1143024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 03/16/2023] [Indexed: 04/05/2023] Open
Abstract
IntroductionNeurons are polarized cells, and their ability to change their morphology has a functional implication in the development and plasticity of the nervous system in order to establish new connections. Extracellular factors strongly influence neuronal shape and connectivity. For instance, the developmental actions of estradiol on hippocampal neurons are well characterized, and we have demonstrated in previous studies that Ngn3 mediates these actions. On the other hand, Kif21B regulates microtubule dynamics and carries out retrograde transport of the TrkB/brain-derived neurotrophic factor (BDNF) complex, essential for neuronal development.MethodsIn the present study, we assessed the involvement of kinesin Kif21B in the estradiol-dependent signaling mechanisms to regulate neuritogenesis through cultured mouse hippocampal neurons.ResultsWe show that estradiol treatment increases BDNF expression, and estradiol and BDNF modify neuron morphology through TrkB signaling. Treatment with K252a, a TrkB inhibitor, decreases dendrite branching without affecting axonal length, whereas. Combined with estradiol or BDNF, it blocks their effects on axons but not dendrites. Notably, the downregulation of Kif21B abolishes the actions of estradiol and BDNF in both the axon and dendrites. In addition, Kif21B silencing also decreases Ngn3 expression, and downregulation of Ngn3 blocks the effect of BDNF on neuron morphology.DiscussionThese results suggest that Kif21B is required for the effects of estradiol and BDNF on neuronal morphology, but phosphorylation-mediated activation of TrkB is essential only for axonal growth. Our results show that the Estradiol/BDNF/TrkB/Kif21B/Ngn3 is a new and essential pathway mediating hippocampal neuron development.
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Affiliation(s)
| | - Daniel Pinto-Benito
- Instituto Cajal (IC), CSIC, Madrid, Spain
- Centro de Investigación Biomédica en Red de Fragilidad y Envejecimiento Saludable (CIBERFES), Instituto de Salud Carlos III, Madrid, Spain
| | | | - Isabel Ruiz-Palmero
- Centro de Investigación Biomédica en Red de Fragilidad y Envejecimiento Saludable (CIBERFES), Instituto de Salud Carlos III, Madrid, Spain
- Servicio de Proteómica, Instituto Biosanitario de Granada-IBS, Fundación Para la Investigación Biosanitaria de Andalucía Oriental—Alejandro Otero (FIBAO), Antiguo Hospital Universitario San Cecilio, Unidad de Apoyo a la Investigación (UNAI), Granada, Spain
| | - Daniela Grassi
- Instituto Cajal (IC), CSIC, Madrid, Spain
- Department of Anatomy, Histology and Neuroscience, Autonoma University of Madrid, Madrid, Spain
| | - Maria Angeles Arevalo
- Instituto Cajal (IC), CSIC, Madrid, Spain
- Centro de Investigación Biomédica en Red de Fragilidad y Envejecimiento Saludable (CIBERFES), Instituto de Salud Carlos III, Madrid, Spain
- *Correspondence: Maria Angeles Arevalo,
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Mulvey B, Frye HE, Lintz T, Fass S, Tycksen E, Nelson EC, Morón JA, Dougherty JD. Cnih3 Deletion Dysregulates Dorsal Hippocampal Transcription across the Estrous Cycle. eNeuro 2023; 10:ENEURO.0153-22.2023. [PMID: 36849260 PMCID: PMC10027183 DOI: 10.1523/eneuro.0153-22.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 02/14/2023] [Accepted: 02/17/2023] [Indexed: 03/01/2023] Open
Abstract
In females, the hippocampus, a critical brain region for coordination of learning, memory, and behavior, displays altered physiology and behavioral output across the estrous or menstrual cycle. However, the molecular effectors and cell types underlying these observed cyclic changes have only been partially characterized to date. Recently, profiling of mice null for the AMPA receptor trafficking gene Cnih3 have demonstrated estrous-dependent phenotypes in dorsal hippocampal synaptic plasticity, composition, and learning/memory. We therefore profiled dorsal hippocampal transcriptomes from female mice in each estrous cycle stage, and contrasted it with that of males, across wild-type (WT) and Cnih3 mutants. In wild types, we identified only subtle differences in gene expression between the sexes, while comparing estrous stages to one another revealed up to >1000 differentially expressed genes (DEGs). These estrous-responsive genes are especially enriched in gene markers of oligodendrocytes and the dentate gyrus, and in functional gene sets relating to estrogen response, potassium channels, and synaptic gene splicing. Surprisingly, Cnih3 knock-outs (KOs) showed far broader transcriptomic differences between estrous cycle stages and males. Moreover, Cnih3 knock-out drove subtle but extensive expression changes accentuating sex differential expression at diestrus and estrus. Altogether, our profiling highlights cell types and molecular systems potentially impacted by estrous-specific gene expression patterns in the adult dorsal hippocampus, enabling mechanistic hypothesis generation for future studies of sex-differential neuropsychiatric function and dysfunction. Moreover, these findings suggest an unrecognized role of Cnih3 in buffering against transcriptional effects of estrous, providing a candidate molecular mechanism to explain estrous-dependent phenotypes observed with Cnih3 loss.
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Affiliation(s)
- Bernard Mulvey
- Department of Genetics, Washington University School of Medicine, St. Louis, MO 63110
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO 63110
| | - Hannah E Frye
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO 63110
| | - Tania Lintz
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO 63110
| | - Stuart Fass
- Department of Genetics, Washington University School of Medicine, St. Louis, MO 63110
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO 63110
| | - Eric Tycksen
- Department of Genetics, Washington University School of Medicine, St. Louis, MO 63110
- McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO 63110
| | - Elliot C Nelson
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO 63110
| | - Jose A Morón
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO 63110
| | - Joseph D Dougherty
- Department of Genetics, Washington University School of Medicine, St. Louis, MO 63110
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO 63110
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Narayan G, Agrawal A, Joshi N, Gogoi R, Nagotu S, Thummer RP. Protein Production and Purification of a Codon-Optimized Human NGN3 Transcription Factor from E. coli. Protein J 2021; 40:891-906. [PMID: 34550497 DOI: 10.1007/s10930-021-10020-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/08/2021] [Indexed: 12/29/2022]
Abstract
Neurogenin 3 (NGN3) transcription factor is vital for the development of endocrine cells of the intestine and pancreas. NGN3 is also critical for the neural precursor cell determination in the neuroectoderm. Additionally, it is one of the vital transcription factors for deriving human β-cells from specialized somatic cells. In the current study, the production and purification of the human NGN3 protein from Escherichia coli (E. coli) is reported. First, the 642 bp protein-coding nucleotide sequence of the NGN3 gene was codon-optimized to enable enhanced protein expression in E. coli strain BL21(DE3). The codon-optimized NGN3 sequence was fused in-frame to three different fusion tags to enable cell penetration, nuclear translocation, and affinity purification. The gene insert with the fusion tags was subsequently cloned into an expression vector (pET28a( +)) for heterologous expression in BL21(DE3) cells. A suitable genetic construct and the ideal expression conditions were subsequently identified that produced a soluble form of the recombinant NGN3 fusion protein. This NGN3 fusion protein was purified to homogeneity (purity > 90%) under native conditions, and its secondary structure was retained post-purification. This purified protein, when applied to human cells, did not induce cytotoxicity. Further, the cellular uptake and nuclear translocation of the NGN3 fusion protein was demonstrated followed by its biological activity in PANC-1 cells. Prospectively, this recombinant protein can be utilized for various biological applications to investigate its functionality in cell reprogramming, biological processes, and diseases.
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Affiliation(s)
- Gloria Narayan
- Laboratory for Stem Cell Engineering and Regenerative Medicine, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, Assam, 781039, India
| | - Akriti Agrawal
- Laboratory for Stem Cell Engineering and Regenerative Medicine, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, Assam, 781039, India
| | - Neha Joshi
- Organelle Biology and Cellular Ageing Lab, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, Assam, 781039, India
| | - Ranadeep Gogoi
- Department of Biotechnology, National Institute of Pharmaceutical Education and Research Guwahati, Changsari, Guwahati, Assam, 781101, India.,CSIR-North East Institute of Science & Technology, Jorhat, Assam, 785006, India
| | - Shirisha Nagotu
- Organelle Biology and Cellular Ageing Lab, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, Assam, 781039, India
| | - Rajkumar P Thummer
- Laboratory for Stem Cell Engineering and Regenerative Medicine, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, Assam, 781039, India.
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Hou Z, Liu X, Jiang W, Hou Z, Yin Y, Xie C, Zhang H, Zhang H, Zhang Z, Yuan Y. Effect of NEUROG3 polymorphism rs144643855 on regional spontaneous brain activity in major depressive disorder. Behav Brain Res 2021; 409:113310. [PMID: 33878431 DOI: 10.1016/j.bbr.2021.113310] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 04/05/2021] [Accepted: 04/15/2021] [Indexed: 11/15/2022]
Abstract
PURPOSE Our previous study identified a significant association between a single nucleotide polymorphism (SNP) located in the neurogenin3 (NEUROG3) gene and post-stroke depression (PSD) in Chinese populations. The present work explores whether polymorphism rs144643855 affects regional brain activity and clinical phenotypes in major depressive disorder (MDD). METHOD A total of 182 participants were included: 116 MDD patients and 66 normal controls. All participants underwent resting-state functional magnetic resonance imaging (rs-fMRI) scanning at baseline. Spontaneous brain activity was assessed using amplitude of low-frequency fluctuation (ALFF). The Hamilton Depression Scale-24 (HAMD-24) and Snaith-Hamilton Pleasure Scale (SHAPS) were used to assess participants at baseline. Two-way analysis of covariance (ANCOVA) was used to explore the interaction between diagnostic groups and NEUROG3 rs144643855 on regional brain activity. We performed correlation analysis to further test the association between these interactive brain regions and clinical manifestations of MDD. RESULTS Genotype and disease significantly interacted in the left inferior frontal gyrus (IFG-L), right superior frontal gyrus (SFG-R), and left paracentral lobule (PCL-L) (P < 0.05). ALFF values of the IFG-L were found to be significantly associated with anhedonia in MDD patients. CONCLUSION These findings suggest a potential relationship between rs144643855 variations and altered frontal brain activity in MDD. NEUROG3 may play an important role in the neuropathophysiology of MDD.
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Affiliation(s)
- Zhuoliang Hou
- Department of Psychosomatics and Psychiatry, ZhongDa Hospital, School of Medical, Southeast University, Nanjing, China
| | - Xiaoyun Liu
- Department of Psychosomatics and Psychiatry, ZhongDa Hospital, School of Medical, Southeast University, Nanjing, China
| | - Wenhao Jiang
- Department of Psychology, Georgia State University, Atlanta, USA
| | - Zhenghua Hou
- Department of Psychosomatics and Psychiatry, ZhongDa Hospital, School of Medical, Southeast University, Nanjing, China
| | - Yingying Yin
- Department of Psychosomatics and Psychiatry, ZhongDa Hospital, School of Medical, Southeast University, Nanjing, China
| | - Chunming Xie
- Department of Neurology, ZhongDa Hospital, School of Medicine, Southeast University, Nanjing, China; The Key Laboratory of Developmental Genes and Human Disease, Southeast University, Nanjing, China
| | - Haisan Zhang
- Departments of Clinical Magnetic Resonance Imaging, the Second Affiliated Hospital of Xinxiang Medical University, Xinxiang, China
| | - Hongxing Zhang
- Departments of Psychiatry, the Second Affiliated Hospital of Xinxiang Medical University, Xinxiang, China
| | - Zhijun Zhang
- Department of Neurology, ZhongDa Hospital, School of Medicine, Southeast University, Nanjing, China; The Key Laboratory of Developmental Genes and Human Disease, Southeast University, Nanjing, China
| | - Yonggui Yuan
- Department of Psychosomatics and Psychiatry, ZhongDa Hospital, School of Medical, Southeast University, Nanjing, China; The Key Laboratory of Developmental Genes and Human Disease, Southeast University, Nanjing, China.
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Cisternas CD, Cabrera Zapata LE, Mir FR, Scerbo MJ, Arevalo MA, Garcia-Segura LM, Cambiasso MJ. Estradiol-dependent axogenesis and Ngn3 expression are determined by XY sex chromosome complement in hypothalamic neurons. Sci Rep 2020; 10:8223. [PMID: 32427857 PMCID: PMC7237695 DOI: 10.1038/s41598-020-65183-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Accepted: 04/14/2020] [Indexed: 01/15/2023] Open
Abstract
Hypothalamic neurons show sex differences in neuritogenesis, female neurons have longer axons and higher levels of the neuritogenic factor neurogenin 3 (Ngn3) than male neurons in vitro. Moreover, the effect of 17-β-estradiol (E2) on axonal growth and Ngn3 expression is only found in male-derived neurons. To investigate whether sex chromosomes regulate these early sex differences in neuritogenesis by regulating the E2 effect on Ngn3, we evaluated the growth and differentiation of hypothalamic neurons derived from the “four core genotypes” mouse model, in which the factors of “gonadal sex” and “sex chromosome complement” are dissociated. We showed that sex differences in neurite outgrowth are determined by sex chromosome complement (XX > XY). Moreover, E2 increased the mRNA expression of Ngn3 and axonal length only in XY neurons. ERα/β expressions are regulated by sex chromosome complement; however, E2-effect on Ngn3 expression in XY neurons was only fully reproduced by PPT, a specific ligand of ERα, and prevented by MPP, a specific antagonist of ERα. Together our data indicate that sex chromosomes regulate early development of hypothalamic neurons by orchestrating not only sex differences in neuritogenesis, but also regulating the effect of E2 on Ngn3 expression through activation of ERα in hypothalamic neurons.
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Affiliation(s)
- Carla Daniela Cisternas
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina.,Departamento de Biología Bucal, Facultad de Odontología -Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Lucas Ezequiel Cabrera Zapata
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Franco Rafael Mir
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
| | - María Julia Scerbo
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
| | - María Angeles Arevalo
- Instituto Cajal, CSIC, Madrid, Spain.,Ciber de Investigación Biomédica en Red de Fragilidad y Envejecimiento Saludable (CIBERFES), Instituto de Salud Carlos III, Madrid, Spain
| | - Luis Miguel Garcia-Segura
- Instituto Cajal, CSIC, Madrid, Spain.,Ciber de Investigación Biomédica en Red de Fragilidad y Envejecimiento Saludable (CIBERFES), Instituto de Salud Carlos III, Madrid, Spain
| | - María Julia Cambiasso
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina. .,Departamento de Biología Bucal, Facultad de Odontología -Universidad Nacional de Córdoba, Córdoba, Argentina.
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Wang L, Sun ZS, Xiang B, Wei CJ, Wang Y, Sun K, Chen G, Lan MS, Carmona GN, Notkins AL, Cai T. Targeted deletion of Insm2 in mice result in reduced insulin secretion and glucose intolerance. J Transl Med 2018; 16:297. [PMID: 30359270 PMCID: PMC6202866 DOI: 10.1186/s12967-018-1665-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Accepted: 10/14/2018] [Indexed: 12/19/2022] Open
Abstract
Background Neurogenin3 (Ngn3) and neurogenic differentiation 1 (NeuroD1), two crucial transcriptional factors involved in human diabetes (OMIM: 601724) and islet development, have been previously found to directly target to the E-boxes of the insulinoma-associated 2 (Insm2) gene promoter, thereby activating the expression of Insm2 in insulin-secretion cells. However, little is known about the function of Insm2 in pancreatic islets and glucose metabolisms. Methods Homozygous Insm2−/− mice were generated by using the CRISPR-Cas9 method. Glucose-stimulated insulin secretion and islet morphology were analyzed by ELISA and immunostainings. Expression levels of Insm2-associated molecules were measured using quantitative RT-PCR and Western blots. Results Fasting blood glucose levels of Insm2−/− mice were higher than wild-type counterparts. Insm2−/− mice also showed reduction in glucose tolerance and insulin/C-peptide levels when compared to the wild-type mice. RT-PCR and Western blot analysis revealed that expression of Insm1 was significantly increased in Insm2−/− mice, suggesting a compensatory response of the homolog gene Insm1. Similarly, transcriptional levels of Ngn3 and NeuroD1 were also increased in Insm2−/− mice. Moreover, Insm2−/− female mice showed a significantly decreased reproductive capacity. Conclusions Our findings suggest that Insm2 is important in glucose-stimulated insulin secretion and is involved in the development pathway of neuroendocrine tissues which are regulated by the transcription factors Ngn3, NeuroD1 and Insm1.
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Affiliation(s)
- Lin Wang
- Institute of Genomic Medicine, Wenzhou Medical University, Wenzhou, China.,Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing, China
| | - Zhong Sheng Sun
- Institute of Genomic Medicine, Wenzhou Medical University, Wenzhou, China. .,Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing, China.
| | - Bingwu Xiang
- Institute of Genomic Medicine, Wenzhou Medical University, Wenzhou, China
| | - Chi-Ju Wei
- Multidisciplinary Research Center, Shantou University, Shantou, Guangdong, China
| | - Yan Wang
- Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing, China
| | - Kevin Sun
- Center for Research on Genomics and Global Health, NHGRI, NIH, Bethesda, MD, USA
| | - Guanjie Chen
- Center for Research on Genomics and Global Health, NHGRI, NIH, Bethesda, MD, USA
| | - Michael S Lan
- Department of Pediatrics, Louisiana State University Health Sciences Center, New Orleans, LA, USA
| | - Gilberto N Carmona
- Experimental Medicine Section, NIDCR, NIH, B30/Rm112, 30 Convent Dr., Bethesda, MD, 20892, USA
| | - Abner L Notkins
- Experimental Medicine Section, NIDCR, NIH, B30/Rm112, 30 Convent Dr., Bethesda, MD, 20892, USA
| | - Tao Cai
- Institute of Genomic Medicine, Wenzhou Medical University, Wenzhou, China. .,Experimental Medicine Section, NIDCR, NIH, B30/Rm112, 30 Convent Dr., Bethesda, MD, 20892, USA.
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8
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Cambiasso MJ, Cisternas CD, Ruiz-Palmero I, Scerbo MJ, Arevalo MA, Azcoitia I, Garcia-Segura LM. Interaction of sex chromosome complement, gonadal hormones and neuronal steroid synthesis on the sexual differentiation of mammalian neurons. J Neurogenet 2017; 31:300-306. [DOI: 10.1080/01677063.2017.1390572] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Maria Julia Cambiasso
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
- Departamento de Biología Bucal, Facultad de Odontología, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Carla Daniela Cisternas
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
- Departamento de Biología Bucal, Facultad de Odontología, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Isabel Ruiz-Palmero
- CSIC, Instituto Cajal, Madrid, Spain
- Centro de Investigación Biomédica en Red de Fragilidad y Envejecimiento Saludable (CIBERFES), Instituto de Salud Carlos III, Madrid, Spain
| | - Maria Julia Scerbo
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
- Departamento de Biología Bucal, Facultad de Odontología, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Maria Angeles Arevalo
- CSIC, Instituto Cajal, Madrid, Spain
- Centro de Investigación Biomédica en Red de Fragilidad y Envejecimiento Saludable (CIBERFES), Instituto de Salud Carlos III, Madrid, Spain
| | - Iñigo Azcoitia
- Centro de Investigación Biomédica en Red de Fragilidad y Envejecimiento Saludable (CIBERFES), Instituto de Salud Carlos III, Madrid, Spain
- Department of Cell Biology, Faculty of Biology, Universidad Complutense, Ciudad Universitaria, Madrid, Spain
| | - Luis M. Garcia-Segura
- CSIC, Instituto Cajal, Madrid, Spain
- Centro de Investigación Biomédica en Red de Fragilidad y Envejecimiento Saludable (CIBERFES), Instituto de Salud Carlos III, Madrid, Spain
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Honoré C, Rescan C, Hald J, McGrath PS, Petersen MBK, Hansson M, Klein T, Østergaard S, Wells JM, Madsen OD. Revisiting the immunocytochemical detection of Neurogenin 3 expression in mouse and man. Diabetes Obes Metab 2016; 18 Suppl 1:10-22. [PMID: 27615127 DOI: 10.1111/dom.12718] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Accepted: 05/08/2016] [Indexed: 12/13/2022]
Abstract
During embryonic development, endocrine cells of the pancreas are specified from multipotent progenitors. The transcription factor Neurogenin 3 (NEUROG3) is critical for this development and it has been shown that all endocrine cells of the pancreas arise from endocrine progenitors expressing NEUROG3. A thorough understanding of the role of NEUROG3 during development, directed differentiation of pluripotent stem cells and in models of cellular reprogramming, will guide future efforts directed at finding novel sources of β-cells for cell replacement therapies. In this article, we review the expression and function of NEUROG3 in both mouse and human and present the further characterization of a monoclonal antibody directed against NEUROG3. This antibody has been previously been used for detection of both mouse and human NEUROG3. However, our results suggest that the epitope recognized by this antibody is specific to mouse NEUROG3. Thus, we have also generated a monoclonal antibody specifically recognizing human NEUROG3 and present the characterization of this antibody here. Together, these antibodies will provide useful tools for future studies of NEUROG3 expression, and the data presented in this article suggest that recently described expression patterns of NEUROG3 in human foetal and adult pancreas should be re-examined.
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Affiliation(s)
- C Honoré
- Department of Islet and Stem Cell Biology, Novo Nordisk A/S, Måløv, Denmark.
| | - C Rescan
- Department of Islet and Stem Cell Biology, Novo Nordisk A/S, Måløv, Denmark
| | - J Hald
- Department of Islet and Stem Cell Biology, Novo Nordisk A/S, Måløv, Denmark
| | - P S McGrath
- Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - M B K Petersen
- Department of Islet and Stem Cell Biology, Novo Nordisk A/S, Måløv, Denmark
| | - M Hansson
- Department of Islet and Stem Cell Biology, Novo Nordisk A/S, Måløv, Denmark
| | - T Klein
- Gubra Aps, Agern Alle 1, Hørsholm, Denmark
| | - S Østergaard
- Department of Islet and Stem Cell Biology, Novo Nordisk A/S, Måløv, Denmark
| | - J M Wells
- Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
- Division of Endocrinology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - O D Madsen
- Department of Islet and Stem Cell Biology, Novo Nordisk A/S, Måløv, Denmark
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10
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Ruiz-Palmero I, Ortiz-Rodriguez A, Melcangi RC, Caruso D, Garcia-Segura LM, Rune GM, Arevalo MA. Oestradiol synthesized by female neurons generates sex differences in neuritogenesis. Sci Rep 2016; 6:31891. [PMID: 27553191 PMCID: PMC4995407 DOI: 10.1038/srep31891] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Accepted: 07/29/2016] [Indexed: 12/04/2022] Open
Abstract
Testosterone produced by the foetal testis is converted by male neurons to oestradiol, which masculinizes neuronal morphology. Female neurons are known to synthesize oestradiol in absence of exogenous testosterone. However, the role of neuronal oestradiol on the differentiation of foetal female neurons is unknown. Here we show that, due to endogenous neuronal oestradiol synthesis, female hippocampal neurons have higher expression of the neuritogenic protein Neurogenin 3 and enhanced neuritogenesis than males. Exogenous application of testosterone or its metabolite dihydrotestosterone increases Neurogenin 3 expression and promotes neuritogenesis in males, but reduces these parameters in females. Together our data indicate that gonadal-independent oestradiol synthesis by female neurons participates in the generation of sex differences in hippocampal neuronal development.
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Affiliation(s)
- Isabel Ruiz-Palmero
- Instituto Cajal, Consejo Superior de Investigaciones Científicas (CSIC), Avenida Doctor Arce 37, 28002 Madrid, Spain
| | - Ana Ortiz-Rodriguez
- Instituto Cajal, Consejo Superior de Investigaciones Científicas (CSIC), Avenida Doctor Arce 37, 28002 Madrid, Spain
| | - Roberto Cosimo Melcangi
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Center of Excellence on Neurodegenerative Diseases, Università degli Studi di Milano, Via G. Balzaretti 9, 20133 Milan, Italy
| | - Donatella Caruso
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Center of Excellence on Neurodegenerative Diseases, Università degli Studi di Milano, Via G. Balzaretti 9, 20133 Milan, Italy
| | - Luis M Garcia-Segura
- Instituto Cajal, Consejo Superior de Investigaciones Científicas (CSIC), Avenida Doctor Arce 37, 28002 Madrid, Spain
| | - Gabriele M Rune
- Institute of Neuroanatomy, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany
| | - Maria-Angeles Arevalo
- Instituto Cajal, Consejo Superior de Investigaciones Científicas (CSIC), Avenida Doctor Arce 37, 28002 Madrid, Spain
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11
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Mellström B, Kastanauskaite A, Knafo S, Gonzalez P, Dopazo XM, Ruiz-Nuño A, Jefferys JGR, Zhuo M, Bliss TVP, Naranjo JR, DeFelipe J. Specific cytoarchitectureal changes in hippocampal subareas in daDREAM mice. Mol Brain 2016; 9:22. [PMID: 26928278 PMCID: PMC4772309 DOI: 10.1186/s13041-016-0204-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Accepted: 02/22/2016] [Indexed: 11/20/2022] Open
Abstract
Background Transcriptional repressor DREAM (downstream regulatory element antagonist modulator) is a Ca2+-binding protein that regulates Ca2+ homeostasis through gene regulation and protein-protein interactions. It has been shown that a dominant active form (daDREAM) is implicated in learning-related synaptic plasticity such as LTP and LTD in the hippocampus. Neuronal spines are reported to play important roles in plasticity and memory. However, the possible role of DREAM in spine plasticity has not been reported. Results Here we show that potentiating DREAM activity, by overexpressing daDREAM, reduced dendritic basal arborization and spine density in CA1 pyramidal neurons and increased spine density in dendrites in dentate gyrus granule cells. These microanatomical changes are accompanied by significant modifications in the expression of specific genes encoding the cytoskeletal proteins Arc, Formin 1 and Gelsolin in daDREAM hippocampus. Conclusions Our results strongly suggest that DREAM plays an important role in structural plasticity in the hippocampus. Electronic supplementary material The online version of this article (doi:10.1186/s13041-016-0204-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Britt Mellström
- Spanish Network for Biomedical Research in Neurodegenerative Diseases, CIBERNED, Madrid, Spain. .,National Biotechnology Center. CSIC, Darwin, 3. E-28049, Madrid, Spain.
| | - Asta Kastanauskaite
- Spanish Network for Biomedical Research in Neurodegenerative Diseases, CIBERNED, Madrid, Spain. .,Cajal Institute, CSIC Madrid, Av Dr. Arce,37 E-28006, Madrid, Spain. .,Biomedical Technology Center, Politecnica University Madrid, Madrid, Spain.
| | - Shira Knafo
- Cajal Institute, CSIC Madrid, Av Dr. Arce,37 E-28006, Madrid, Spain. .,Present address: IkerBasque Basque Foundation for Science and BioCruces, Health Research Institute, Bizkaia, Spain.
| | - Paz Gonzalez
- Spanish Network for Biomedical Research in Neurodegenerative Diseases, CIBERNED, Madrid, Spain. .,National Biotechnology Center. CSIC, Darwin, 3. E-28049, Madrid, Spain.
| | - Xose M Dopazo
- Spanish Network for Biomedical Research in Neurodegenerative Diseases, CIBERNED, Madrid, Spain. .,National Biotechnology Center. CSIC, Darwin, 3. E-28049, Madrid, Spain.
| | - Ana Ruiz-Nuño
- Neuronal Networks Group, School of Clinical and Experimental Medicine, University of Birmingham, Birmingham, UK.
| | - John G R Jefferys
- Neuronal Networks Group, School of Clinical and Experimental Medicine, University of Birmingham, Birmingham, UK.
| | - Min Zhuo
- Department of Physiology, Faculty of Medicine, University of Toronto, 1 King's College Circle, Toronto, Ontario, Canada. .,Center for Neuron and Disease, Frontier Institute of Science and Technology, Xi'an Jiaotong University, Xi'an, China.
| | - Tim V P Bliss
- MRC National Institutes for Medical Research, Mill Hill, London, UK.
| | - Jose R Naranjo
- Spanish Network for Biomedical Research in Neurodegenerative Diseases, CIBERNED, Madrid, Spain. .,National Biotechnology Center. CSIC, Darwin, 3. E-28049, Madrid, Spain.
| | - Javier DeFelipe
- Spanish Network for Biomedical Research in Neurodegenerative Diseases, CIBERNED, Madrid, Spain. .,Cajal Institute, CSIC Madrid, Av Dr. Arce,37 E-28006, Madrid, Spain. .,Biomedical Technology Center, Politecnica University Madrid, Madrid, Spain.
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12
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Masjkur J, Poser SW, Nikolakopoulou P, Chrousos G, McKay RD, Bornstein SR, Jones PM, Androutsellis-Theotokis A. Endocrine Pancreas Development and Regeneration: Noncanonical Ideas From Neural Stem Cell Biology. Diabetes 2016; 65:314-30. [PMID: 26798118 DOI: 10.2337/db15-1099] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Loss of insulin-producing pancreatic islet β-cells is a hallmark of type 1 diabetes. Several experimental paradigms demonstrate that these cells can, in principle, be regenerated from multiple endogenous sources using signaling pathways that are also used during pancreas development. A thorough understanding of these pathways will provide improved opportunities for therapeutic intervention. It is now appreciated that signaling pathways should not be seen as "on" or "off" but that the degree of activity may result in wildly different cellular outcomes. In addition to the degree of operation of a signaling pathway, noncanonical branches also play important roles. Thus, a pathway, once considered as "off" or "low" may actually be highly operational but may be using noncanonical branches. Such branches are only now revealing themselves as new tools to assay them are being generated. A formidable source of noncanonical signal transduction concepts is neural stem cells because these cells appear to have acquired unusual signaling interpretations to allow them to maintain their unique dual properties (self-renewal and multipotency). We discuss how such findings from the neural field can provide a blueprint for the identification of new molecular mechanisms regulating pancreatic biology, with a focus on Notch, Hes/Hey, and hedgehog pathways.
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Affiliation(s)
- Jimmy Masjkur
- Department of Internal Medicine III, Technische Universität Dresden, Dresden, Germany
| | - Steven W Poser
- Department of Internal Medicine III, Technische Universität Dresden, Dresden, Germany
| | | | - George Chrousos
- First Department of Pediatrics, University of Athens Medical School and Aghia Sophia Children's Hospital, Athens, Greece
| | | | - Stefan R Bornstein
- Department of Internal Medicine III, Technische Universität Dresden, Dresden, Germany
| | - Peter M Jones
- Diabetes Research Group, Division of Diabetes & Nutritional Sciences, King's College London, London, U.K
| | - Andreas Androutsellis-Theotokis
- Department of Internal Medicine III, Technische Universität Dresden, Dresden, Germany Center for Regenerative Therapies Dresden, Dresden, Germany Department of Stem Cell Biology, Centre for Biomolecular Sciences, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham, Nottingham, U.K.
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13
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Chacón PJ, del Marco Á, Arévalo Á, Domínguez-Giménez P, García-Segura LM, Rodríguez-Tébar A. Cerebellin 4, a synaptic protein, enhances inhibitory activity and resistance of neurons to amyloid-β toxicity. Neurobiol Aging 2015; 36:1057-71. [DOI: 10.1016/j.neurobiolaging.2014.11.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Revised: 10/29/2014] [Accepted: 11/10/2014] [Indexed: 01/09/2023]
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14
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Scerbo MJ, Freire-Regatillo A, Cisternas CD, Brunotto M, Arevalo MA, Garcia-Segura LM, Cambiasso MJ. Neurogenin 3 mediates sex chromosome effects on the generation of sex differences in hypothalamic neuronal development. Front Cell Neurosci 2014; 8:188. [PMID: 25071448 PMCID: PMC4086225 DOI: 10.3389/fncel.2014.00188] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Accepted: 06/19/2014] [Indexed: 01/01/2023] Open
Abstract
The organizational action of testosterone during critical periods of development is the cause of numerous sex differences in the brain. However, sex differences in neuritogenesis have been detected in primary neuronal hypothalamic cultures prepared before the peak of testosterone production by fetal testis. In the present study we assessed the hypothesis of that cell-autonomous action of sex chromosomes can differentially regulate the expression of the neuritogenic gene neurogenin 3 (Ngn3) in male and female hypothalamic neurons, generating sex differences in neuronal development. Neuronal cultures were prepared from male and female E14 mouse hypothalami, before the fetal peak of testosterone. Female neurons showed enhanced neuritogenesis and higher expression of Ngn3 than male neurons. The silencing of Ngn3 abolished sex differences in neuritogenesis, decreasing the differentiation of female neurons. The sex difference in Ngn3 expression was determined by sex chromosomes, as demonstrated using the four core genotypes mouse model, in which a spontaneous deletion of the testis-determining gene Sry from the Y chromosome was combined with the insertion of the Sry gene onto an autosome. In addition, the expression of Ngn3, which is also known to mediate the neuritogenic actions of estradiol, was increased in the cultures treated with the hormone, but only in those from male embryos. Furthermore, the hormone reversed the sex differences in neuritogenesis promoting the differentiation of male neurons. These findings indicate that Ngn3 mediates both cell-autonomous actions of sex chromosomes and hormonal effects on neuritogenesis.
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Affiliation(s)
- María J Scerbo
- Laboratory of Neurophysiology, Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET - Universidad Nacional de Córdoba Córdoba, Argentina
| | | | - Carla D Cisternas
- Laboratory of Neurophysiology, Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET - Universidad Nacional de Córdoba Córdoba, Argentina ; Departamento de Biología Bucal, Facultad de Odontología - Universidad Nacional de Córdoba Córdoba, Argentina
| | - Mabel Brunotto
- Departamento de Biología Bucal, Facultad de Odontología - Universidad Nacional de Córdoba Córdoba, Argentina
| | - Maria A Arevalo
- Instituto Cajal, Consejo Superior de Investigaciones Científicas Madrid, Spain
| | | | - María J Cambiasso
- Laboratory of Neurophysiology, Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET - Universidad Nacional de Córdoba Córdoba, Argentina ; Departamento de Biología Bucal, Facultad de Odontología - Universidad Nacional de Córdoba Córdoba, Argentina
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15
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Yuan L, Hassan BA. Neurogenins in brain development and disease: an overview. Arch Biochem Biophys 2014; 558:10-3. [PMID: 24950022 DOI: 10.1016/j.abb.2014.05.028] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Revised: 05/25/2014] [Accepted: 05/28/2014] [Indexed: 11/25/2022]
Abstract
The production of neurons, astrocytes and oligodendrocytes is regulated by a group of transcription factors, which determine cell fates and specify subtype identities in the nervous system. Here we focus on profiling the distinct roles of Neurogenin (Ngn or Neurog) family members during the neuronal development. Ngn proteins are tightly regulated to be expressed at defined times and positions of different progenitor cell pools. In addition to their well-elucidated proneural function, Ngn proteins play various critical roles to specify or maintain cell fate and regulate neurite outgrowth and targeting in the central nervous system. Finally, Ngns have been associated with neuronal disorders. Therefore understanding the function and regulation of Ngns will not only improve the understanding of the molecular mechanism underlying the development of nervous system, but may also provide insight into neuronal disease.
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Affiliation(s)
- Liqun Yuan
- VIB Center for the Biology of Disease, VIB, 3000 Leuven, Belgium; Center for Human Genetics, University of Leuven School of Medicine, 3000 Leuven, Belgium
| | - Bassem A Hassan
- VIB Center for the Biology of Disease, VIB, 3000 Leuven, Belgium; Center for Human Genetics, University of Leuven School of Medicine, 3000 Leuven, Belgium.
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16
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Bonini SA, Ferrari-Toninelli G, Montinaro M, Memo M. Notch signalling in adult neurons: a potential target for microtubule stabilization. Ther Adv Neurol Disord 2013; 6:375-85. [PMID: 24228073 DOI: 10.1177/1756285613490051] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Cytoskeletal dysfunction has been proposed during the last decade as one of the main mechanisms involved in the aetiology of several neurodegenerative diseases. Microtubules are basic elements of the cytoskeleton and the dysregulation of microtubule stability has been demonstrated to be causative for axonal transport impairment, synaptic contact degeneration, impaired neuronal function leading finally to neuronal loss. Several pathways are implicated in the microtubule assembly/disassembly process. Emerging evidence is focusing on Notch as a microtubule dynamics regulator. We demonstrated that activation of Notch signalling results in increased microtubule stability and changes in axonal morphology and branching. By contrast, Notch inhibition leads to an increase in cytoskeleton plasticity with intense neurite remodelling. Until now, several microtubule-binding compounds have been tested and the results have provided proof of concept that microtubule-binding agents or compounds with the ability to stabilize microtubules may have therapeutic potential for the treatment of Alzheimer's disease and other neurodegenerative diseases. In this review, based on its key role in cytoskeletal dynamics modulation, we propose Notch as a new potential target for microtubule stabilization.
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Affiliation(s)
- Sara Anna Bonini
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
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17
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Ruiz-Palmero I, Hernando M, Garcia-Segura LM, Arevalo MA. G protein-coupled estrogen receptor is required for the neuritogenic mechanism of 17β-estradiol in developing hippocampal neurons. Mol Cell Endocrinol 2013; 372:105-15. [PMID: 23545157 DOI: 10.1016/j.mce.2013.03.018] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2012] [Revised: 02/28/2013] [Accepted: 03/21/2013] [Indexed: 01/29/2023]
Abstract
Estradiol promotes neuritogenesis in developing hippocampal neurons by a mechanism involving the upregulation of neurogenin 3, a Notch-regulated transcription factor. In this study we have explored whether G-protein coupled estrogen receptor 1 (GPER) participates in this hormonal action. GPER agonists (17β-estradiol, G1, ICI 182,780) increased neurogenin 3 expression and neuritogenesis in mouse primary hippocampal neurons and this effect was blocked by the GPER antagonist G15 and by a siRNA for GPER. In addition, GPER agonists increased Akt phosphorylation in ser473, which is indicative of the activation of phosphoinositide-3-kinase (PI3K). G15 or GPER silencing prevented the estrogenic induction of Akt phosphorylation. Furthermore, the PI3K inhibitor wortmannin prevented the effect of G1 and estradiol on neurogenin 3 expression and the effect of estradiol on neuritogenesis. These findings suggest that GPER participates in the control of hippocampal neuritogenesis by a mechanism involving the activation of PI3K signaling.
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18
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Notch signaling pathway is activated in motoneurons of spinal muscular atrophy. Int J Mol Sci 2013; 14:11424-37. [PMID: 23759991 PMCID: PMC3709740 DOI: 10.3390/ijms140611424] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Revised: 05/02/2013] [Accepted: 05/17/2013] [Indexed: 02/07/2023] Open
Abstract
Spinal muscular atrophy (SMA) is a neurodegenerative disease produced by low levels of Survival Motor Neuron (SMN) protein that affects alpha motoneurons in the spinal cord. Notch signaling is a cell-cell communication system well known as a master regulator of neural development, but also with important roles in the adult central nervous system. Aberrant Notch function is associated with several developmental neurological disorders; however, the potential implication of the Notch pathway in SMA pathogenesis has not been studied yet. We report here that SMN deficiency, induced in the astroglioma cell line U87MG after lentiviral transduction with a shSMN construct, was associated with an increase in the expression of the main components of Notch signaling pathway, namely its ligands, Jagged1 and Delta1, the Notch receptor and its active intracellular form (NICD). In the SMNΔ7 mouse model of SMA we also found increased astrocyte processes positive for Jagged1 and Delta1 in intimate contact with lumbar spinal cord motoneurons. In these motoneurons an increased Notch signaling was found, as denoted by increased NICD levels and reduced expression of the proneural gene neurogenin 3, whose transcription is negatively regulated by Notch. Together, these findings may be relevant to understand some pathologic attributes of SMA motoneurons.
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19
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Simon-Areces J, Acaz-Fonseca E, Ruiz-Palmero I, Garcia-Segura LM, Arevalo MA. A CRM1-mediated nuclear export signal is essential for cytoplasmic localization of neurogenin 3 in neurons. PLoS One 2013; 8:e55237. [PMID: 23383123 PMCID: PMC3559332 DOI: 10.1371/journal.pone.0055237] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2012] [Accepted: 12/27/2012] [Indexed: 01/13/2023] Open
Abstract
Neurogenin 3 (Ngn3), a proneural gene, regulates dendritogenesis and synaptogenesis in mouse hippocampal neurons. Ngn3 is transiently exported from the cell nucleus to the cytoplasm when neuronal polarity is initiated, suggesting that the nucleo-cytoplasmic transport of the protein is important for its action on neuronal development. In this study, we identified for the first time a functional nuclear export sequence (NES2; ¹³¹YIWALTQTLRIA¹⁴²) in Ngn3. The green fluorescent protein (EGFP)-NES2 fusion protein was localized in the cytoplasm and its nucleo-cytoplasmic shuttling was blocked by the CRM1 specific export inhibitor leptomycin B. Mutation of a leucine residue to alanine (L135A) in the NES2 motif resulted in both cytoplasmic and nuclear localization of the EGFP-NES2 fusion protein and in the nuclear accumulation of ectopic full-length myc-Ngn3. In addition, point mutation of the leucine 135 counteracted the effects of Ngn3 on neuronal morphology and synaptic inputs indicating that the cytoplasmic localization of Ngn3 is important for neuronal development. Pharmacological perturbation of the cytoskeleton revealed that cytoplasmic Ngn3 is associated with microtubules.
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20
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Roark R, Itzhaki L, Philpott A. Complex regulation controls Neurogenin3 proteolysis. Biol Open 2012; 1:1264-72. [PMID: 23259061 PMCID: PMC3522888 DOI: 10.1242/bio.20121750] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2012] [Accepted: 08/01/2012] [Indexed: 12/21/2022] Open
Abstract
The ubiquitin proteasome system (UPS) is known to be responsible for the rapid turnover of many transcription factors, where half-life is held to be critical for regulation of transcriptional activity. However, the stability of key transcriptional regulators of development is often very poorly characterised. Neurogenin 3 (Ngn3) is a basic helix–loop–helix transcription factor that plays a central role in specification and differentiation of endocrine cells of the pancreas and gut, as well as spermatogonia and regions of the brain. Here we demonstrate that Ngn3 protein stability is regulated by the ubiquitin proteasome system and that Ngn3 can be ubiquitylated on lysines, the N-terminus and, highly unusually, on non-canonical residues including cysteines and serines/threonines. Rapid turnover of Ngn3 is regulated both by binding to its heterodimeric partner E protein and by the presence of cdk inhibitors. We show that protein half-life does appear to regulate the activity of Ngn3 in vivo, but, unlike the related transcription factor c-myc, ubiquitylation on canonical sites is not a requirement for transcriptional activity of Ngn3. Hence, we characterise an important new level of Ngn3 post-translational control, which may regulate its transcriptional activity.
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Affiliation(s)
- Ryan Roark
- Department of Oncology, University of Cambridge, Hutchison/Medical Research Council (MRC) Research Centre , Cambridge CB2 0XZ , UK
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21
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Simon-Areces J, Dietrich MO, Hermes G, Garcia-Segura LM, Arevalo MA, Horvath TL. UCP2 induced by natural birth regulates neuronal differentiation of the hippocampus and related adult behavior. PLoS One 2012; 7:e42911. [PMID: 22905184 PMCID: PMC3414493 DOI: 10.1371/journal.pone.0042911] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2011] [Accepted: 07/16/2012] [Indexed: 12/15/2022] Open
Abstract
Mitochondrial uncoupling protein 2 (UCP2) is induced by cellular stress and is involved in regulation of fuel utilization, mitochondrial bioenergetics, cell proliferation, neuroprotection and synaptogenesis in the adult brain. Here we show that natural birth in mice triggers UCP2 expression in hippocampal neurons. Chemical inhibition or genetic ablation of UCP2 lead to diminished neuronal number and size, dendritic growth and synaptogenezis in vitro and impaired complex behaviors in the adult. These data reveal a critical role for Ucp2 expression in the development of hippocampal neurons and circuits and hippocampus-related adult behaviors.
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Affiliation(s)
| | - Marcelo O. Dietrich
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Section of Comparative Medicine, Yale University School of Medicine, New Haven, Connecticut, United States of America
- Department of Biochemistry, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Gretchen Hermes
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Section of Comparative Medicine, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | | | | | - Tamas L. Horvath
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Section of Comparative Medicine, Yale University School of Medicine, New Haven, Connecticut, United States of America
- Department of Biochemistry, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
- Departments of Neurobiology and Obstetrics, Gynecology and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut, United States of America
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22
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Arevalo MA, Ruiz-Palmero I, Scerbo MJ, Acaz-Fonseca E, Cambiasso MJ, Garcia-Segura LM. Molecular mechanisms involved in the regulation of neuritogenesis by estradiol: Recent advances. J Steroid Biochem Mol Biol 2012; 131:52-6. [PMID: 21971420 DOI: 10.1016/j.jsbmb.2011.09.004] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2011] [Revised: 09/19/2011] [Accepted: 09/21/2011] [Indexed: 12/13/2022]
Abstract
This review analyzes the signaling mechanisms activated by estradiol to regulate neuritogenesis in several neuronal populations. Estradiol regulates axogenesis by the activation of the mitogen activated protein kinase (MAPK) cascade through estrogen receptor α located in the plasma membrane. In addition, estradiol regulates MAPK signaling via the activation of protein kinase C and by increasing the expression of brain derived neurotrophic factor and tyrosine kinase receptor B. Estradiol also interacts with the signaling of insulin-like growth factor-I receptor through estrogen receptor α, modulating the phosphoinositide-3 kinase signaling pathway, which contributes to the stabilization of microtubules. Finally, estradiol modulates dendritogenesis by the inhibition of Notch signaling, by a mechanism that, at least in hippocampal neurons, is mediated by G-protein coupled receptor 30. This article is part of a Special Issue entitled 'Neurosteroids'.
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23
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Swales N, Martens GA, Bonné S, Heremans Y, Borup R, Van de Casteele M, Ling Z, Pipeleers D, Ravassard P, Nielsen F, Ferrer J, Heimberg H. Plasticity of adult human pancreatic duct cells by neurogenin3-mediated reprogramming. PLoS One 2012. [PMID: 22606327 DOI: 10.137/journal.pone.0037055] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
AIMS/HYPOTHESIS Duct cells isolated from adult human pancreas can be reprogrammed to express islet beta cell genes by adenoviral transduction of the developmental transcription factor neurogenin3 (Ngn3). In this study we aimed to fully characterize the extent of this reprogramming and intended to improve it. METHODS The extent of the Ngn3-mediated duct-to-endocrine cell reprogramming was measured employing genome wide mRNA profiling. By modulation of the Delta-Notch signaling or addition of pancreatic endocrine transcription factors Myt1, MafA and Pdx1 we intended to improve the reprogramming. RESULTS Ngn3 stimulates duct cells to express a focused set of genes that are characteristic for islet endocrine cells and/or neural tissues. This neuro-endocrine shift however, is incomplete with less than 10% of full duct-to-endocrine reprogramming achieved. Transduction of exogenous Ngn3 activates endogenous Ngn3 suggesting auto-activation of this gene. Furthermore, pancreatic endocrine reprogramming of human duct cells can be moderately enhanced by inhibition of Delta-Notch signaling as well as by co-expressing the transcription factor Myt1, but not MafA and Pdx1. CONCLUSIONS/INTERPRETATION The results provide further insight into the plasticity of adult human duct cells and suggest measurable routes to enhance Ngn3-mediated in vitro reprogramming protocols for regenerative beta cell therapy in diabetes.
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Affiliation(s)
- Nathalie Swales
- Diabetes Research Center, Vrije Universiteit Brussel, Brussels, Belgium
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Swales N, Martens GA, Bonné S, Heremans Y, Borup R, Van de Casteele M, Ling Z, Pipeleers D, Ravassard P, Nielsen F, Ferrer J, Heimberg H. Plasticity of adult human pancreatic duct cells by neurogenin3-mediated reprogramming. PLoS One 2012; 7:e37055. [PMID: 22606327 PMCID: PMC3351393 DOI: 10.1371/journal.pone.0037055] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2011] [Accepted: 04/16/2012] [Indexed: 12/01/2022] Open
Abstract
Aims/Hypothesis Duct cells isolated from adult human pancreas can be reprogrammed to express islet beta cell genes by adenoviral transduction of the developmental transcription factor neurogenin3 (Ngn3). In this study we aimed to fully characterize the extent of this reprogramming and intended to improve it. Methods The extent of the Ngn3-mediated duct-to-endocrine cell reprogramming was measured employing genome wide mRNA profiling. By modulation of the Delta-Notch signaling or addition of pancreatic endocrine transcription factors Myt1, MafA and Pdx1 we intended to improve the reprogramming. Results Ngn3 stimulates duct cells to express a focused set of genes that are characteristic for islet endocrine cells and/or neural tissues. This neuro-endocrine shift however, is incomplete with less than 10% of full duct-to-endocrine reprogramming achieved. Transduction of exogenous Ngn3 activates endogenous Ngn3 suggesting auto-activation of this gene. Furthermore, pancreatic endocrine reprogramming of human duct cells can be moderately enhanced by inhibition of Delta-Notch signaling as well as by co-expressing the transcription factor Myt1, but not MafA and Pdx1. Conclusions/Interpretation The results provide further insight into the plasticity of adult human duct cells and suggest measurable routes to enhance Ngn3-mediated in vitro reprogramming protocols for regenerative beta cell therapy in diabetes.
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Affiliation(s)
- Nathalie Swales
- Diabetes Research Center, Vrije Universiteit Brussel, Brussels, Belgium
| | - Geert A. Martens
- Diabetes Research Center, Vrije Universiteit Brussel, Brussels, Belgium
| | - Stefan Bonné
- Diabetes Research Center, Vrije Universiteit Brussel, Brussels, Belgium
| | - Yves Heremans
- Diabetes Research Center, Vrije Universiteit Brussel, Brussels, Belgium
| | - Rehannah Borup
- Microarray Facility, Rigshospitalet, Copenhagen, Denmark
| | | | - Zhidong Ling
- Diabetes Research Center, Vrije Universiteit Brussel, Brussels, Belgium
| | - Daniel Pipeleers
- Diabetes Research Center, Vrije Universiteit Brussel, Brussels, Belgium
| | - Philippe Ravassard
- Centre de Recherche Institut du Cerveau et de la Moelle, CNRS UMR7225, Université Pierre et Marie Curie, Paris, France
| | - Finn Nielsen
- Microarray Facility, Rigshospitalet, Copenhagen, Denmark
| | - Jorge Ferrer
- Genomic Programming of Beta Cells Laboratory, Institut d’Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain
| | - Harry Heimberg
- Diabetes Research Center, Vrije Universiteit Brussel, Brussels, Belgium
- * E-mail:
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Swales N, Martens GA, Bonné S, Heremans Y, Borup R, Van de Casteele M, Ling Z, Pipeleers D, Ravassard P, Nielsen F, Ferrer J, Heimberg H. Plasticity of adult human pancreatic duct cells by neurogenin3-mediated reprogramming. PLoS One 2012. [PMID: 22606327 DOI: 10.137/journal.pone.0037055.] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
AIMS/HYPOTHESIS Duct cells isolated from adult human pancreas can be reprogrammed to express islet beta cell genes by adenoviral transduction of the developmental transcription factor neurogenin3 (Ngn3). In this study we aimed to fully characterize the extent of this reprogramming and intended to improve it. METHODS The extent of the Ngn3-mediated duct-to-endocrine cell reprogramming was measured employing genome wide mRNA profiling. By modulation of the Delta-Notch signaling or addition of pancreatic endocrine transcription factors Myt1, MafA and Pdx1 we intended to improve the reprogramming. RESULTS Ngn3 stimulates duct cells to express a focused set of genes that are characteristic for islet endocrine cells and/or neural tissues. This neuro-endocrine shift however, is incomplete with less than 10% of full duct-to-endocrine reprogramming achieved. Transduction of exogenous Ngn3 activates endogenous Ngn3 suggesting auto-activation of this gene. Furthermore, pancreatic endocrine reprogramming of human duct cells can be moderately enhanced by inhibition of Delta-Notch signaling as well as by co-expressing the transcription factor Myt1, but not MafA and Pdx1. CONCLUSIONS/INTERPRETATION The results provide further insight into the plasticity of adult human duct cells and suggest measurable routes to enhance Ngn3-mediated in vitro reprogramming protocols for regenerative beta cell therapy in diabetes.
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Affiliation(s)
- Nathalie Swales
- Diabetes Research Center, Vrije Universiteit Brussel, Brussels, Belgium
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Simon-Areces J, Dopazo A, Dettenhofer M, Rodriguez-Tebar A, Garcia-Segura LM, Arevalo MA. Formin1 mediates the induction of dendritogenesis and synaptogenesis by neurogenin3 in mouse hippocampal neurons. PLoS One 2011; 6:e21825. [PMID: 21818269 PMCID: PMC3139584 DOI: 10.1371/journal.pone.0021825] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2011] [Accepted: 06/13/2011] [Indexed: 11/21/2022] Open
Abstract
Neurogenin3, a proneural transcription factor controlled by Notch receptor, has been recently shown to regulate dendritogenesis and synaptogenesis in mouse hippocampal neurons. However, little is known about the molecular mechanisms involved in these actions of Ngn3. We have used a microarray analysis to identify Ngn3 regulated genes related with cytoskeleton dynamics. One of such genes is Fmn1, whose protein, Formin1, is associated with actin and microtubule cytoskeleton. Overexpression of the Fmn1 isoform-Ib in cultured mouse hippocampal neurons induced an increase in the number of primary dendrites and in the number of glutamatergic synaptic inputs at 4 days in vitro. The same changes were provoked by overexpression of Ngn3. In addition downregulation of Fmn1 by the use of Fmn1-siRNAs impaired such morphological and synaptic changes induced by Ngn3 overexpression in neurons. These results reveal a previously unknown involvement of Formin1 in dendritogenesis and synaptogenesis and indicate that this protein is a key component of the Ngn3 signaling pathway that controls neuronal differentiation.
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Affiliation(s)
- Julia Simon-Areces
- Laboratory of Neuroactive Steroids, Instituto Cajal, Consejo Superior de Investigaciones Cientificas (CSIC), Madrid, Spain
| | - Ana Dopazo
- Genomics Unit, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
| | - Markus Dettenhofer
- Department of Genetics, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Alfredo Rodriguez-Tebar
- Centro Andaluz de Biología Molecular y Medicina Regenerativa/Consejo Superior de Investigaciones Cientificas (CABIMER/CSIC), Seville, Spain
| | - Luis Miguel Garcia-Segura
- Laboratory of Neuroactive Steroids, Instituto Cajal, Consejo Superior de Investigaciones Cientificas (CSIC), Madrid, Spain
| | - Maria-Angeles Arevalo
- Laboratory of Neuroactive Steroids, Instituto Cajal, Consejo Superior de Investigaciones Cientificas (CSIC), Madrid, Spain
- * E-mail:
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Ables JL, Breunig JJ, Eisch AJ, Rakic P. Not(ch) just development: Notch signalling in the adult brain. Nat Rev Neurosci 2011; 12:269-83. [PMID: 21505516 DOI: 10.1038/nrn3024] [Citation(s) in RCA: 322] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The Notch pathway is often regarded as a developmental pathway, but components of Notch signalling are expressed and active in the adult brain. With the advent of more sophisticated genetic manipulations, evidence has emerged that suggests both conserved and novel roles for Notch signalling in the adult brain. Not surprisingly, Notch is a key regulator of adult neural stem cells, but it is increasingly clear that Notch signalling also has roles in the regulation of migration, morphology, synaptic plasticity and survival of immature and mature neurons. Understanding the many functions of Notch signalling in the adult brain, and its dysfunction in neurodegenerative disease and malignancy, is crucial to the development of new therapeutics that are centred around this pathway.
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Affiliation(s)
- Jessica L Ables
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
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Ruiz-Palmero I, Simon-Areces J, Garcia-Segura LM, Arevalo MA. Notch/neurogenin 3 signalling is involved in the neuritogenic actions of oestradiol in developing hippocampal neurones. J Neuroendocrinol 2011; 23:355-64. [PMID: 21251092 DOI: 10.1111/j.1365-2826.2011.02110.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The ovarian hormone oestradiol promotes neuritic outgrowth in different neuronal types, by mechanisms that remain elusive. Recent studies have shown that the Notch-regulated transcription factor neurogenin 3 controls neuritogenesis. In the present study, we assessed whether oestradiol regulates neurogenin 3 in primary hippocampal neurones. As expected, neuritogenesis was increased in the cultures treated with oestradiol. However, the neuritogenic action of oestradiol was not prevented by ICI 182,780, an antagonist of classical oestrogen receptors (ERs). Oestradiol decreased the expression of Hairy and Enhancer of Split-1, a Notch-regulated gene that negatively controls the expression on neurogenin 3. Furthermore, oestradiol increased the expression of neurogenin 3 and regulated its distribution between the neuronal cell nucleus and the cytoplasm. The effect of oestradiol on neurogenin 3 expression was not blocked by antagonists of classical nuclear ER-mediated transcription and was not imitated by selective agonists of nuclear ERs. By contrast, G1, a ligand of G protein receptor 30/G protein-coupled ER, fully reproduced the effect of oestradiol on neuritogenesis, neurogenin 3 expression and neurogenin 3 subcellular localisation. Moreover, knockdown of neurogenin 3 in neurones by transfection with small interference RNA for neurogenin 3 completely abrogated the neuritogenic actions of oestradiol and G1. These results suggest that oestradiol regulates neurogenin 3 in primary hippocampal neurones by a nonclassical steroid signalling mechanism, which involves the down-regulation of Notch activity and the activation of G protein receptor 30/G protein-coupled ER or of other unknown G1 targets. In addition, our findings indicate that neurogenin 3 participates in the neuritogenic mechanisms of oestradiol in hippocampal neurones.
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